Ultrasonics
Encyclopedia
Ultrasonics is a term meaning the application of ultrasound. It is often used in industry as a shorthand term for any equipment employing ultrasonic principles.
Ultrasonics is also a trade term coined by the Ultrasonic Manufacturers Association and used by its successor, the Ultrasonic Industry Association, to refer to the use of high-intensity acoustic energy to change materials [reference required and evidence of earliest usage of this term]. This usage is contrasted to ultrasound
, which is generally reserved for imaging, as in sonar
, materials examination (NDI), and diagnostics (mammography
, duplex ultrasonography, etc.). The term "ultrasonic" is, however, common to both fields, for example
Ultrasonication offers great potential in the processing of liquids and slurries, by improving the mixing and chemical reactions in various applications and industries. Ultrasonication generates alternating low-pressure and high-pressure waves in liquids, leading to the formation and violent collapse of small vacuum
bubbles. This phenomenon is termed cavitation
and causes high speed impinging liquid jets and strong hydrodynamic shear-forces. These effects are used for the deagglomeration and milling of micrometre and nanometre-size materials as well as for the disintegration of cells or the mixing of reactants. In this aspect, ultrasonication is an alternative to high-speed mixers and agitator bead mills. Ultrasonic foils under the moving wire in a paper machine will use the shock waves from the imploding bubbles to distribute the cellulose fibres more uniform in the produced paper web, which will make a stronger paper with more even surfaces. Furthermore, chemical reactions benefit from the free radicals created by the cavitation as well as from the energy input and the material transfer through boundary layers. For many processes, this sonochemical (see sonochemistry
) effect leads to a substantial reduction the reaction time, like in the transesterification
of oil into biodiesel
.
Ultrasonication can easily be tested in lab scale for its effect on various liquid formulations. Equipment manufacturers have developed a number of larger ultrasonic processors of up to 16 kW power. Therefore volumes from 1mL up to several hundred gallons per minute can be sonicated today in order to achieve all kinds of results from the link that is shown below.
Ultrasonic technology was for over 40 years employed in the steel industry, initially with flaw detection and later joined by wall thickness measurement.
For the past 15 years the plastics industry has used ultrasonic testing in the field of wall thickness measurement of pipe extrusions.
Quality considerations and material savings serve as arguments for investment in and protection against the increasingly important aspect of product liability. Also, Automation increasingly is being used in order to facilitate the use of data to recalculate the production costs of individual products and optimize the entire plant from this.
In the last few years, considerable efforts were made to utilize ultrasonic wall thickness measuring systems in the pipe extrusion. This ultimately was demonstrated by a multitude of key patents.
Ultrasonics is also a trade term coined by the Ultrasonic Manufacturers Association and used by its successor, the Ultrasonic Industry Association, to refer to the use of high-intensity acoustic energy to change materials [reference required and evidence of earliest usage of this term]. This usage is contrasted to ultrasound
Ultrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...
, which is generally reserved for imaging, as in sonar
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
, materials examination (NDI), and diagnostics (mammography
Mammography
Mammography is the process of using low-energy-X-rays to examine the human breast and is used as a diagnostic and a screening tool....
, duplex ultrasonography, etc.). The term "ultrasonic" is, however, common to both fields, for example
- Ultrasonic Flaw Detection for Technicians, 3rd ed., 2004 by J. C. Drury
- Ultrasonic nondestructive evaluation : engineering and biological material characterization, Boca Raton, FL : CRC Press, c2004, by Tribikram Kundu
Ultrasonication offers great potential in the processing of liquids and slurries, by improving the mixing and chemical reactions in various applications and industries. Ultrasonication generates alternating low-pressure and high-pressure waves in liquids, leading to the formation and violent collapse of small vacuum
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
bubbles. This phenomenon is termed cavitation
Cavitation
Cavitation is the formation and then immediate implosion of cavities in a liquidi.e. small liquid-free zones that are the consequence of forces acting upon the liquid...
and causes high speed impinging liquid jets and strong hydrodynamic shear-forces. These effects are used for the deagglomeration and milling of micrometre and nanometre-size materials as well as for the disintegration of cells or the mixing of reactants. In this aspect, ultrasonication is an alternative to high-speed mixers and agitator bead mills. Ultrasonic foils under the moving wire in a paper machine will use the shock waves from the imploding bubbles to distribute the cellulose fibres more uniform in the produced paper web, which will make a stronger paper with more even surfaces. Furthermore, chemical reactions benefit from the free radicals created by the cavitation as well as from the energy input and the material transfer through boundary layers. For many processes, this sonochemical (see sonochemistry
Sonochemistry
In chemistry, the study of sonochemistry is concerned with understanding the effect of sonic waves and wave properties on chemical systems. The chemical effects of ultrasound do not come from adirect interaction with molecular species...
) effect leads to a substantial reduction the reaction time, like in the transesterification
Transesterification
In organic chemistry, transesterification is the process of exchanging the organic group R″ of an ester with the organic group R′ of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst...
of oil into biodiesel
Biodiesel
Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....
.
Ultrasonication can easily be tested in lab scale for its effect on various liquid formulations. Equipment manufacturers have developed a number of larger ultrasonic processors of up to 16 kW power. Therefore volumes from 1mL up to several hundred gallons per minute can be sonicated today in order to achieve all kinds of results from the link that is shown below.
Ultrasonic technology was for over 40 years employed in the steel industry, initially with flaw detection and later joined by wall thickness measurement.
For the past 15 years the plastics industry has used ultrasonic testing in the field of wall thickness measurement of pipe extrusions.
Quality considerations and material savings serve as arguments for investment in and protection against the increasingly important aspect of product liability. Also, Automation increasingly is being used in order to facilitate the use of data to recalculate the production costs of individual products and optimize the entire plant from this.
- Material Saving
- Automation
- Quality Control
In the last few years, considerable efforts were made to utilize ultrasonic wall thickness measuring systems in the pipe extrusion. This ultimately was demonstrated by a multitude of key patents.